Our project needs to manage multiple systems across multiple operating systems and languages (Windows, Linux, Java, C++, C#, etc). We're looking at WMI for parts of the system, but for some of the Java pieces expose JMX interfaces for management. Are there any tools that could consolidate the management of these systems or ease the integration of WMI with JMX?

I use SpiceWorks for Windows and Linux management. It's free and they are constantly adding new features. WMI configs can be hard to get working right on XP, but Vista and Windows 7 is much easier. For Linux management, spiceworks uses ssh which is easy to setup.